I have a 2004 mondeo tdci which has started randomly cutting out, can happen when sitting idle, or at 70 goin down the motorway.

only happens once every couple of weeks and normally doesn't start for five or ten minutes then bursts back into life as if nothing is wrong. had it on a couple of diagnostics and no fault codes are coming up.

I would go with the crank angle sensor, whip it out and see if there is any debris stuck to it (it is a magnet!), if there is then it could be the DMF on its way.....the debris stops a strong enough signal going back to the ecu, sometimes it will cause the car to not rev above 3000 rev's, other times it will rev ok when the engine gets warm.
Worth a look!